Baby No. 5 will join an ensemble cast at family gatherings that includes youngest sons Raoul Meyer Jr., 23, and Douglas Meyer, 25, whose father is Nielsen's fourth husband, Raoul Meyer; 28-year-old Killian Gastineau, the son of former New York Jets great Mark Gastineau; and Julian Winding, 34, the son of musician and Nielsen's first husband, Kasper Winding.